testutils: print a helpful summary of failed tests
testutils: print a helpful summary of failed tests

When debugging test failures in seven independent test
cases, it might be helpful to only gather the debug output
of the failing cases.

Record the indexes of the tests that fail and print them
in the VIR_TEST_RANGE of the command line that will result
in only those tests being run.

Signed-off-by: Ján Tomko <4cab11cfb98d3c937327354a78eb07dbb6ee2bc6@redhat.com>
Reviewed-by: Daniel P. Berrangé <bb938cf255e055ff3507f2627d214e8e62118fcf@redhat.com>

jardasgit/libvirt,jfehlig/libvirt,libvirt/libvirt,jardasgit/libvirt,olafhering/libvirt,crobinso/libvirt,zippy2/libvirt,libvirt/libvirt,nertpinx/libvirt,jfehlig/libvirt,nertpinx/libvirt,jardasgit/libvirt,fabianfreyer/libvirt,zippy2/libvirt,crobinso/libvirt,olafhering/libvirt,nertpinx/libvirt,olafhering/libvirt,jardasgit/libvirt,jardasgit/libvirt,jfehlig/libvirt,fabianfreyer/libvirt,fabianfreyer/libvirt,nertpinx/libvirt,crobinso/libvirt,zippy2/libvirt,libvirt/libvirt,fabianfreyer/libvirt,crobinso/libvirt,zippy2/libvirt,nertpinx/libvirt,libvirt/libvirt,jfehlig/libvirt,fabianfreyer/libvirt,olafhering/libvirt